The present invention relates to a joint member and a method of forming a joint between two stepped cementitious surfaces. It is of particular relevance to the joints in concrete floors.
Conventional concrete floors may require a joint system to allow for movement. There are a variety of known method of forming such joints: sealing joints with an elastomer to allow for movement; using an epoxy sealant; using a combination of the two types of fillers; or any of the above methods with a saw cut through the jointing material to allow for movement. These styles of filling provide support for the cementitious faces of the joint, but do not perform well or are expensive to construct.
An improvement in the method of forming a joint and the joint member to fit in a joint are disclosed in New Zealand Patent Nos 229154 and 247968. The method disclosed incorporates the insertion of an elongate divider plate means between two faces in a groove, channel or slot, the plate means having projections which bear against but not into the cementitious faces in order to provide two regions filled with a settable material. The joint member of New Zealand Patent No 247968 discloses such a divider plate means, with projections sloping upwardly and outwardly from a base to hold the joint member in place.
However both the method and the joint member described above cannot be used where the cementitious faces are necked, stepped or shouldered so that the joint, in cross-section, has two different widths. The use of, or creation of, such a cross-section and a joint member for use therein can be used to reduce the amount of setting material required, permit an increase in the width of a joint that can be repaired/made; and increase the range of joints which can be filled and thus protected from wear and tear of the edges of the blocks in a floor.